Patent EP0418533A1 successfully refreshed from Google Patents.
EP0418533A1
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EP
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Process for purifying polyether-polyols
Assignee: Linde GmbH
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Filing: 1990-08-06
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Granted: —
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Expires: 2010-08-06
Abstract
Abstract The present invention relates to a process for purifying polyether-polyols. The heretofore mainly used methods, which were based on the neutralization with acids and the use of several adsorbents, offer drawbacks ranging from the possibility of corrosion to the need of a plurality of filtrations, carried out with the use of filtering aids. The present invention consists in treating the polyether-polyols, in the presence of water, with an alkalies adsorbent (acidic clays such as, e.g., a clay of montmorillonite type which was treated with inorganic acids), and in subsequently submitting them to a dehydration and to one single filtration without using a filtering aid.
Inventors
- 👤 Amabile Penati
- 👤 Enrico Moretti
- 👤 Carlo Maffezzoni
- 👤 Garbis Agopian
- 👤 Boyan Georgiev Mazdrakov
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 15:24
CPC Classifications
C; C08; C08G; C08G65/00; C08G65/02; C08G65/30
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
104 words
A process for neutralizing and purifying polyether-polyols of the kind providing the treatment of said polyether-polyols with water and an alkalies adsorbent material and their filtration, characterized in that it comprises the following steps: (a) adding to the polyether-polyol, with stirring, under a nitrogen blanketing atmosphere, an amount of water comprised within the range of 0,1 to 10%; (b) adding to the reaction mixture still being kept stirred, and under a nitrogen blanketing atmosphere, at least one clay with acidic character or an acid treated clay as alkalies adsorbent and alkalies neutralizing agent; (c) distilling off water under vacuum and filtering the reaction mixture.
Claim 2
Dependent Claim
104 words
A process for neutralizing and purifying polyether-polyols of the kind providing the treatment of said polyether-polyols with water and an alkalies adsorbent material and their filtration, characterized in that it comprises the following steps: (a) adding to the polyether-polyol, with stirring, under a nitrogen blanketing atmosphere, an amount of water comprised within the range of 0,1 to 10%; (b) adding to the reaction mixture still being kept stirred, and under a nitrogen blanketing atmosphere, at least one clay with acidic character or an acid treated clay as alkalies adsorbent and alkalies neutralizing agent; (c) distilling off water under vacuum and filtering the reaction mixture.
Claim 3
Dependent Claim
20 words
A process according to claim 1, characterized in that the water is distilled off under vacuum before filtering the mixture.
Claim 4
Dependent Claim
23 words
A process according to claims 1 and 2, characterized in that the alkalies adsorbent and neutralizing agent is montmorillonite clay treated with acids.
Claim 5
Dependent Claim
37 words
A process according to claim 3, characterized in that said clay is added in an amount within the range from 0,5 to 4,0% by weight of the polyether-polyol, depending on the amount of the alkalyne catalyst used.
Claim 6
Dependent Claim
23 words
A process according to any preceding claim, characterized in that the filtration is carried out directly, in the absence of any filtering aids.
Claim 7
Dependent Claim
23 words
Use of acidic clays or of acid treated clays as alkalies adsorbent and neutralizing agent in the purification of polyether-polyols from alkaline catalysts.
Claim 8
Dependent Claim
23 words
Use of acidic clays or of acid treated clays as alkalies adsorbent and neutralizing agent in the purification of polyether-polyols from alkaline catalysts.
References Cited (Backward Citations)
US4029879A
Cited
EP0006107A1
Cited
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